Trending
CVE-2026-42533

CVE detail

CVE-2026-42533

A vulnerability exists in NGINX Plus and NGINX Open Source when a map directive uses regex matching and a string expression references the map's regex capture variables before referencing the map output variable. Alternatively, the same result could be achieved by using a non-cacheable variable in a string expression under certain conditions. An unauthenticated attacker along with conditions beyond their control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Impact: This vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system or to possibly trigger a code execution. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS 9.2 · CriticalBuzz score 48.61 public exploit repository references

Buzz score

Why this CVE is surfacing

Buzz score total 48.6

This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.

Buzz score components · mention 25.6 · diversity 18.0 · KEV 0.0 · OTX 0.0 · PoC 5.0

Mention score

25.6

12 evidence mentions in the snapshot

Diversity score

18.0

5 sources across 3 categories

KEV score

0.0

No KEV entry observed

OTX score

0.0

0 OTX pulses

PoC score

5.0

1 repos · best confidence 0.99

Best PoC traction

Maximum stars on a matched PoC repo

Why it matters now

Mention timeline

Total mentions: 8; within the 30d window
Peak daily: 3; highest bucket

Evidence

Source links by recency

Newest mentions first

12 source links · newest first

Security Affairs newsletter Round 587 by Pierluigi Paganini – INTERNATIONAL EDITIONSecurity Affairs
lized AI Model for Vulnerability Hunting Check Point patches actively exploited SmartConsole authentication bypass flaw CVE-2026-8933: Ubuntu security flaw breaks Snap sandbox protections Adobe Acrobat Chrome extension bug enabled silent WhatsApp data theft U.S. CISA adds DD-WRT, Langflow and WordPress flaws to its Known Exploited Vulnerabilities cata
newssecurityaffairs.comJul 26, 2026, 11:42 AM
Google Released Gemini 3.5 Flash Cyber AI, a Specialized AI Model for Vulnerability HuntingSecurity Affairs
d AI Model for Vulnerability Hunting | Check Point patches actively exploited SmartConsole authentication bypass flaw | CVE-2026-8933: Ubuntu security flaw breaks Snap sandbox protections | Adobe Acrobat Chrome extension bug enabled silent WhatsApp data theft | U.S. CISA adds DD-WRT, Langflow and WordPress flaws to its Known Exploited Vulnerabilities
newssecurityaffairs.comJul 23, 2026, 11:44 AM
OpenAI AI models exploited zero-days to reach Hugging Face in benchmark testSecurity Affairs
d AI Model for Vulnerability Hunting | Check Point patches actively exploited SmartConsole authentication bypass flaw | CVE-2026-8933: Ubuntu security flaw breaks Snap sandbox protections | Adobe Acrobat Chrome extension bug enabled silent WhatsApp data theft | U.S. CISA adds DD-WRT, Langflow and WordPress flaws to its Known Exploited Vulnerabilities
newssecurityaffairs.comJul 22, 2026, 8:51 AM
CVE-2026-42533 NGINX Map directive and Regex matching vulnerabilityMicrosoft MSRC
Information published.
vendormsrc.microsoft.comJul 22, 2026, 8:41 AM
Zimbra 10.1.20 patches multiple security issues, including a critical command injection bugSecurity Affairs
d AI Model for Vulnerability Hunting | Check Point patches actively exploited SmartConsole authentication bypass flaw | CVE-2026-8933: Ubuntu security flaw breaks Snap sandbox protections | Adobe Acrobat Chrome extension bug enabled silent WhatsApp data theft | U.S. CISA adds DD-WRT, Langflow and WordPress flaws to its Known Exploited Vulnerabilities
newssecurityaffairs.comJul 21, 2026, 6:25 PM
⚡ Weekly Recap: WordPress RCE, SonicWall 0-Days, AI Service Attacks, SharePoint 0-Day and MoreThe Hacker News
on a standard WordPress installation, without requiring any plugins or other special conditions. It is a combination of CVE-2026-63030 (REST API batch-route confusion) and CVE-2026-60137 (SQL injection in WordPress core) that can be chained to turn an anonymous request into code execution. watchTowr said it's already seeing proof-of-concept (PoC) explo
newsthehackernews.comJul 20, 2026, 1:32 PM
CVE-2026-42533: Critical NGINX Bug Could Turn HTTP Requests Into Server TakeoversSecurity Affairs
F5 fixes critical nginx flaw CVE-2026-42533 that can crash servers and, in some cases, allow remote code execution through crafted HTTP requests. F5 released patches for a critical nginx vulnerability, tracked as CVE-2026-42533 (CVSS score of 9.2), that can allow
newssecurityaffairs.comJul 20, 2026, 9:50 AM
AI Agents Turned Into Attackers: Hugging Face Reveals Autonomous Intrusion CampaignSecurity Affairs
Contact me MUST READ Critical 7-Zip Flaw Allows Code Execution by Opening Crafted XZ-Compressed Files. Update it now! | CVE-2026-42533: Critical NGINX Bug Could Turn HTTP Requests Into Server Takeovers | AI Agents Turned Into Attackers: Hugging Face Reveals Autonomous Intrusion Campaign | Volexity Uncovers Zero-Day Campaign Targeting SonicWall VPN Appl
newssecurityaffairs.comJul 20, 2026, 8:21 AM
Critical NGINX Vulnerability Can Crash Workers and May Allow Remote Code ExecutionThe Hacker News
ets a remote, unauthenticated attacker trigger a heap buffer overflow in the worker process with crafted HTTP requests. CVE-2026-42533 was patched on July 15 in nginx 1.30.4 (stable) and 1.31.3 (mainline), and in NGINX Plus 37.0.3.1; anyone on an earlier build should upgrade. Triggering it can crash or restart the worker, causing a denial of
newsthehackernews.comJul 19, 2026, 8:42 PM
OpenSSL Fixes HollowByte Memory Exhaustion BugSecurity Affairs
Contact me MUST READ Critical 7-Zip Flaw Allows Code Execution by Opening Crafted XZ-Compressed Files. Update it now! | CVE-2026-42533: Critical NGINX Bug Could Turn HTTP Requests Into Server Takeovers | AI Agents Turned Into Attackers: Hugging Face Reveals Autonomous Intrusion Campaign | Volexity Uncovers Zero-Day Campaign Targeting SonicWall VPN Appl
newssecurityaffairs.comJul 18, 2026, 6:24 PM
F5 Patches Multiple NGINX, BIG-IP VulnerabilitiesSecurityWeek
nounced an out-of-band security rollout that patches eight vulnerabilities in NGINX and BIG-IP. The most severe flaw is CVE-2026-42533 (CVSS score of 9.2), a critical issue in NGINX Plus and NGINX Open Source that could be exploited via crafted HTTP requests to cause a heap buffer overflow and restart the NGINX worker process. “A vulnerability exists i
newswww.securityweek.comJul 16, 2026, 9:20 AM
https://my.f5.com/manage/s/article/K000162097my.f5.com
No excerpt available.
Vendor Advisorymy.f5.comJul 15, 2026, 3:16 PM

Exploit code

Public exploit repository references

Public PoC repositories are third-party, potentially unsafe artifacts. Treat their code as untrusted and use it only on authorized systems in an isolated, least-privilege environment. cvebuzz does not execute the code or verify that an exploit works.

1 repository references · best confidence 0.99 · max 0 stars

gagaltotal/CVE-2026-42533-nginxHigh confidence
githubRepository topic discovery0 starsDiscovered Jul 23, 2026, 10:51 AM

Related records

Similar CVEs

6 related CVEs with shared weakness or product evidence

CVE-2026-42055
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2…
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CVE-2026-9256
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when a rewrite directive uses a regex pattern with distinct,…
CVSS 9.2 · Critical
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CVE-2026-42945
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or…
CVSS 9.2 · Critical
Public PoC observed48 mentions
CVE-2026-60005
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_slice_module module. When the slice directive and unnamed regex captures are configured or when a background…
CVSS 8.8 · High
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CVE-2026-60065
When NGINX Plus is configured to use the Message Queuing Telemetry Transport (MQTT) filter module (ngx_stream_mqtt_filter_module), unauthenticated attackers can send requests with…
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1 mention
CVE-2026-56434
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_bu…
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3 mentions

External lookup

Potential internet exposure

Potential exposure only — not proof of vulnerability.Shodan results indicate potentially internet-exposed products, not confirmed vulnerable systems. They do not confirm that any returned system is vulnerable to CVE-2026-42533.

Product-level CPE searches intentionally omit version fields and NVD version-range or configuration certainty. Verify the exact product version and configuration independently.

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Product CPE queries

Derived from this CVE's existing NVD CPE 2.3 records; the application, operating-system, or hardware part is retained.

cpe:2.3:a:f5:nginx_gateway_fabricSearch this product on Shodan
cpe:2.3:a:f5:nginx_ingress_controllerSearch this product on Shodan
cpe:2.3:a:f5:nginx_plusSearch this product on Shodan
cpe:2.3:a:f5:wafSearch this product on Shodan

Exact CVE query

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Metadata

Canonical fields

NVD status

Analyzed

Published

Jul 15, 2026

Modified

Aug 10, 2026

Official record

Authoritative NVD record

CVSS vector

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CWE IDs

Vendor classifications

How this vector reads

CVSS 4.0 base metrics decoded below. This explanation does not recalculate or change the NVD score.

Attack Vector (AV): Network. The vulnerable system can be reached across network boundaries.
Attack Complexity (AC): High. Successful exploitation depends on conditions outside the attacker's control.
Attack Requirements (AT): None. No prerequisite deployment or execution condition is required.
Privileges Required (PR): None. The attacker needs no privileges on the vulnerable system.
User Interaction (UI): None. Exploitation does not require a targeted user to act.
Vulnerable System Confidentiality (VC): High. There is a total or serious impact to this security property.
Vulnerable System Integrity (VI): High. There is a total or serious impact to this security property.
Vulnerable System Availability (VA): High. There is a total or serious impact to this security property.
Subsequent System Confidentiality (SC): None. There is no direct impact to this security property.
Subsequent System Integrity (SI): None. There is no direct impact to this security property.
Subsequent System Availability (SA): None. There is no direct impact to this security property.

Optional CVSS v4 metrics remain in the raw vector; only base metrics are expanded here.

Signals

Exploitation indicators

0 stored signals · no KEV · 0 OTX pulses